Closure device for container opening



1 Nov. 12, 19 40.

H. w. DODSON 2,220,893 CLOSURE DEVICE FOR CONTAINER OPENING 7 Filed Feb.8. 19:9

Patented Nov. 12, 1940 UNlTED STATES PATENT OFFICE Howard W. Dodson.Philadelphia, Pa.. minor to United Steel Barrel Company, Philadelphia,Pa., a corporations! Pennsylvania Application February 8, 1939, SerialNo. 255,201

3 Claims.

The present invention relates to closure devices for the openings ofmetallic containers, such as drums, barrels, cans, tanks, or the like,and particularly for the openings through which 5 such containers,drums, barrels, tanks, etc., may

be filled and emptied.

The present invention relates more particularly to openings and closuredevices therefor which are to be repeatedly opened or closed, or inwhich the closure device is to be secured by screw threads or similarmeans.

In sheet metal containers, such as steel drums, barrels, tanks,sheet-metal cans, many means have been devised in the past for outliningthe opening through the thin sheet-metal with a grommet-likethread-bearing member sometimes referred to as a flange or as a bushing,as shown for instance in the following patents: Nos. 473,495; 643,743;689,896; 817,100; 1,486,374;

435; 1,901,196; 1,915,300; 1,982,144; 1,982,145; and 2,021,960. As thecost of production is frequently a vital :factor bearing upon thepracticability of the device, particularly where the container. such asthe sheet-metal drum; barrel, tank, or the like is likely to be usedonly once for the transportation or storage of the original contents, itis important to provide not only effective closure means, but also onewhich can be produced at low cost and which can be made produced at lowcost and which can be made uniform by manufacturing operations notsubject to failure.

Thus, as such closures for containers must be made in large quantities,it is important that the construction shall be one which will bedependable in mass production.

One of the objects of the present invention is to provide a so-calledflange end closure for 0 sheet-metal containers, such as drums, barrels,tanks, etc., which will be bothdependable and will bear a low productioncost, and in which the possibilities of failure either in themanufacture or in use of the device will be minimized.

With the above and other objects in view which will appear more fullyfrom the following detailed description, the present inventioncontemplates a screw-threaded flange for the openings of sheet-metalcontainers, such as steel drums, barrels, etc., separate and distinctfrom the body metal of the container, and indeed of a metal differentfrom the body metal and which is formed in a molten state directly uponthe body metal of the container and surrounding its opening.

More particularly, the present invention contemplates casting a flange,in situ, directly to the opening in the body metal which is to serve asthe filling or emptying opening of the container, and so interlockingthe cast flange with the peripheral zone of the body metal as to formafirmunion therebetween.

The present invention further consists of other novel features,principles and details of construction all of which will appear morefully from the following detailed description.

For the purpose of illustrating the invention, there is shown in theaccompanying drawing forms thereof which are at present preferred, sincethe same have been found in practice to give satisfactory and reliableresults, although it is to be understood that the variousinstrumentalities of which the invention consists can be variouslyarranged and organized, and that the invention is not limited to theprecise arrangement and organization of the instrumentalities as hereinshown and described.

In the accompanying drawing in which like reference characters indicatelike parts,

Figure 1 represents a fragmentary perspective cross-sectional view ofthe drum head and flange enclosure, representing one embodiment of thepresent invention.

Figure 2 represents a cross-sectional view of a drum headand flangeenclosure representing a somewhat modified form of the presentinvention.

Figure 3 represents a fragmentary cross-sectional view of a modifiedform of construction similar to that shown in Figures 1 and 2.

Figure 4 represents a sectional view of a drum head and flange enclosureof still another embodiment of the present invention.

Figure 5 represents a fragmentary perspective cross-sectional view ofthe drum head and flange illustrated in Figure 4, showing anotherembodiment of the present invention.

Figure 6 represents a fragmentary cross secview of the inturnedperipheral portion of the body metal in the embodiment shown in Figure8, to show the notching thereof.

Figure represents a fragmentary cross-se- 5 tional view of anotherembodiment of the present invention.

Figure 11 represents a fragmentary cross-sectional view of anotherembodiment of the present invention.

Figure 12 represents a fragmentary cross-sectional view of anotherembodiment of the present invention.

The present invention contemplates forming a hole in the sheet metal ofthe head or body of the container. In the particular illustration shownthe body sheet-metal or body metal is indicated as being that of thehead or generally fiat end of the sheet-metal container, such as thedrum, barrel, tank, can, etc., although it is to be understood that thepresent invention is equally applicable to openings in. the more or lesscylindrical sides of such containers.

The opening indicated generally by the numeral 2i is first preferablyprepared so as to present some interruptions in the continuity of themetal in the zone of the periphery of the opening 2i. Thus, forinstance, the zone around the periphery of the opening may be perforatedwith a series of more or less staggered openings 22, or by more or lesssimilar indentations or corrugations pressed into the body metal 20 inthe peripheral zone 23 thereof. The width of such peripheral zone may bevaried. Thus, it may be considerably narrower than that shown in Figure1, as for instance, that shown in Figures 3, 4, 5, 6 and 9.

I then apply to the opening 2i in the body metal 20 a mold having aconcavity or metalreceiving space of the cross-section and size of anyof the flange, as for instance, those indicated in Figures 1 to 8,inclusive.

A relatively low melting-point alloy, consisting principally of zincwith variable amounts of aluminum, copper and magnesium and, optional-1y, with some per centages of tin and antimony, is then poured or forcedinto the mold under pressure in a molten stage and at a sufllcient temperature, so that it will flow freely and fill the mold completely andso that the screw threads 24 of. the flange, designated generally by thenumeral 25 will be sharply and clearly defined and so that the metalwill enter the interlocking interruptions, as for instance the holes 22in the peripheral zone 23 of the body metal 20,

The construction of the molds and the manner of their application to theopenings 2| in the body metal 20 is not here shown because thisspecification is intended to be addressed solely to the resultantproduct and the method of. making the 0 same (and not to the apparatusfor making the same and not to the apparatus for the practice of themethod). I

A low-melting point alloy composition for the flanges 25 may berepresented by a composition of 90. to 95% zinc and about 2 to 5%aluminum,

1 to 4% copper and about .01 to .05% of magnesium. These proportions maybe varied according to the degree of hardness and other qualitiesdesired.

.The peripheral zone 23 of the body metal 20 or some part thereof isalso preferably turned or pressed at an angle to the main part of thebody metal in the manner indicated in Figures 1 to 9 inclusive, so thatan annular web designated gen- 7 erally by the numeral 26 is formed atan angle to the main part of the body metal 23 and extending more orless parallel to the imaginary cylinder which would be defined by thepitch line of the screw thread before. Thus, instead of merely havingthe body metal terminate in a plane opening as in Figure 10, theinnermost portion of the peripheral zone of the body metal around thehole or opening 2i is either turned inwardly or outwardly. In the formsof construction shown in Figures 1, 2, 3, 4, 5, 6, 7, 8 and i 9, thisperipheral portion is turned inwardly,

while in the form of construction shown in Figure 5, the web 26 isturned outwardly. It is to be understood that each of the various formsof webs shown in the several views such as that shown in Figures 1 and 2and that shown in Figures 4, 5 and 6 and that shown in Figures 8 and 9,can be turned outwardly instead of inwardly, as shown in theserespective flgures;the difference being that the die-cast metal of theflange 25 will extend to engage such web.

In the forms of construction indicated in Figures 4, 5, 6 and 11, theweb 26 is more or less crimped or corrugated with successive spaceportions 21 bent outwardly or inwardly and out of line with the rest ofthe web 26 in the manner shown in Figure 5 and indicated by the dottedlines in Figures 4, 6 and 11, so that the metal of the flange 25 whichis cast in situ will follow these interruptions in the otherwise smoothperiphery of the web so as to form an interlock therewith which willtend to prevent relative rotation between flange 25 and body 20.

Alternative to this crimping, holes 22 may be provided in the web 25, inthe general manner indicated in Figures 1, 2, 3 and '7, through whichthe die-cast metal of the flange 25 extends.

As a further alternative, the web 26 may be notched as at 28 by cuttingout small portions preferably at the same time the opening in the bodymetal is punched.

The flange 25 may be provided with a gasketseating surface, as forinstance, the surface 29 against which the sealing gasket 30 may bepressed by the screw plug 3| in the manner indicated in Figure 2.

The gasket-seating surface may be recessed or lowered as at 32 in Figure1 for reducing the distance to which the plug and final seal mustproject beyond the outer surface of the body metal 20.

Alternative to the seating of the gasket 30 upon the flange, the flangemay be formed below the adjoining or contiguous outer surface 33 of thebody metal as indicated in Figures 4, 5, 6, 7 and 8, so that the gasket30 may be pressed directly against the body metal, as shown particularlyin Figures 4 and 5. By so providing a gasket seat on the body metal, thefluid-tight seal will not be affected by any possible cracking orfracture of the die-cast flange 25. Thus, for instance, in the forms ofconstruction shown in Figures 4, 5, 6, 7 and 8, the flange may becomefractured anywhere throughout its periphery and may be broken completelythrough at one or more points without affecting the seal of the gasket30 because the seal is made directly against a continuous anduninterrupted body metal surface 33. Thus, a fracture or breakage of theannular die-cast flange 25 at one or more points of its circumferencewill not release the plug 3i because the successive sections of theflange produced by such fracture will still be maintained by the web 26as well as by the plug 3i. Thus,in addition to the interlocking betweenthe die-cast metal of the flange 25 and the web 28, the plug 3| alsotends to pull the flange 25 into tight contact with the body metalrather than to separate it therefrom.

If desired, as for instance, in the forms of construction shown inFigures 1, '2 and 3, as well as in the other form of construction, anonmetallic or part-metallic sealing gasket 34 may be placed against thebody metal and pressed against it and embedded partly in the die-castmetal so as further to insure a continuous fluidtight or gas-tightsealing between body metal and die-cast flange-metal. This gasket 34 maybe of a fibrous material suitably impregnated and compressed. Ifdesired, also, a narrow ring of fluid or plastic sealing compounds maybe substituted in place of or added to augment the sealing gasket 34 andpermitted to set or harden sufficiently prior to the application of themolten metal of the flange 25 so that the sealing compound will remainin place during the application of the molten metal and will sealagainstboth the body metal as well as the die-cast metal.

Before the application of the molten metal to form the flange 25, thebody metal (at least in the zone of the application of the flange metal)is preferably-cleaned of all scale. In this manner a substantialadhesion or union or metal-to-. metal bonding may be obtained betweenthe molten flange metal and the body metal. This union or bonding may befurther augmented or increased by initially turning or, cadmium orzinc-coating or plating the body metal in the zone where the flange isto be applied thereto. By increasing the union or the metal-to metalbonding between body metal and flange metal. the web interruptionsindicated bythe apertures 22 and notches 21 and 28 may be reduced innumber or extent or may be omitted.

I may, however, combine both' the metal-tometal bonding featureshereinabove described with the web interruptions indicated by theapertures 22 or the notches 21 or 20. Such metalto metal bonding alsotends to effect a fluid-tight or gas-tight seal between body metal andflange metal.

' After the plug 3| or the plug 25 is applied to the flange 25 andtightened in place, itmay be desirable to apply some tamper-proof ortamperindicating lock or sealing means, and as a further modification ofthe present invention, I contemplate casting a perforated lug Iintegrally with the flange 25, as for instance, shown in Figure 2 andprovide a hole 31 through one comer of the plug, through which a sealingwire may be extended which is then threaded through the hole 20 in thelug l. A lead or other metallic seal may then be applied to the wire soas to prevent the unscrewingof the plug ll without detection. 1

By forming the flange-28 with an outer inclined or horizontal shoulder38 or 40 (Figure 2 and Figure 3) .a crimped sheet metal sealing cap 4|may also be superimposed upon the plug, with its peripheral edge portion42 crimped under the shoulder 20 or 40 by any suitable crimping tube, soas completely to prevent access to the plug Ii or 8| duringtransportation or storage. If

the flange II is provided with 9. lug 3| as indicatedin Figures 1 and2., then the periphery of.

the cap 4| is cut out as at 4| sumciently to clear the I: 34-.

In crimped cap 4|. the crimped flange thereof is so opened up as to makeits application impossible without detection.

If desired, a second gasket seat 45 may be provided for receiving asecond gasket 46 between the flange 25 and the cap 4| in the mannerindicated generally in Figure 1.

If it is desired to apply a sealing cap similar to the sealing cap 4|shown in Figures 1, 2 and 3, to the form of construction in. which themain gasket seating surface 33 is on the body metal as shown in Figures4, 5, 6, 7, 8 and 11, then the body metal may be pressed to form anannular inclined or undercut shoulder, either of the intemal form 41 asin Figures 4 and- 5, or of the external form 48 in Figures 6, 7, 8 and11. The cap 4| of the general form shown in Figure 2 is then applied inthe manner shown in Figure 6 with its crimped periphery 42 crimpeddirectly against the under-cut shoulder 48 on the body metal. With theinternal form of shoulder 41 the cap 4i is of the outwardly expandingtype shown in Figure 4 with the peripheral portion 42 thereof spreadoutwardly either by initial tension or by spreading pressure appliedvertically from above to an initially flared peripheral edge 42.

The present invention may be embodied in other specific forms withoutdeparting from the spirit or essential attributes thereof, and it istherefore desired that the present embodiments be considered in allrespects as illustrative and not restrictive, reference being had to theappended claims rather than to the foregoing description to indicate thescope of the invention.

Having thus described the invention, what is hereby claimed as new anddesired to be secured by Letters Patent is:

1. In a sheet-metal container having a relatively small opening formedin a wall'thereof, a metallic thread-carrying bushing of a lower meltingpoint metal pressure-cast, in situ, outlining said opening andenveloping a peripheral zone of the sheet-metal side wall of saidcontainer adjacent said opening.

2. In a sheet-metal container having a relatively small opening formedin a wallthereof,

a metallic thread-carrying bushing of a lower immediately surroundingsaid opening and disposed. 'at least in part, in a plane different fromthat of the wall in which the opening is formed, so as to stiffen theperipheral zone of said open ing, an annular metallic thread-carryingbushing of a lower melting point metal. pressure-cast, in situ,outlining said opening and enveloping a peripheral zone of the sheetun'etal directly adjacent the periphery of said opening and confined to.the aforesaid stiifening acne, and keying recesses in the envelopedportion of said sheet-steel. v

HOWARD W. DOD SON.

